title: Extranodal malignant lymphoma: detection with FDG PET versus CT.
abstract: OBJECTIVE
  To evaluate use of functional imaging with positron emission tomography (PET) versus computed tomography (CT) for detection of extranodal lymphoma spread.
  
  
  METHODS
  Eighty-one consecutive and previously untreated patients with malignant non-Hodgkin lymphoma (n = 43) or Hodgkin disease (n = 38) were examined with 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) PET and contrast material-enhanced CT. Concordant findings at both CT and FDG PET were regarded as actual locations of disease; discordant results were resolved on the basis of biopsy or follow-up results when possible.
  
  
  RESULTS
  Forty-two lesions were identified at both PET and CT, and 19 were verified with biopsy results. PET demonstrated a further 24 lesions. Verification was possible in 15 of these lesions with biopsy (n = 10), magnetic resonance imaging (n = 1), scintigraphic (n = 1), or follow-up (n = 3) results. In 14 of these 15 lesions, PET findings were confirmed (bone marrow, nine; spleen, three; other, two). Seven lesions not visualized at FDG PET were identified at CT, six of which were verified with biopsy (n = 2) or follow-up (n = 4) results. Five of these six CT findings were found to be erroneous. In 13 patients, PET findings led to changes in tumor staging.
  
  
  CONCLUSIONS
  PET may provide more information about extranodal lymphoma than does incremental CT.
authors.affiliation: Department of Nuclear Medicine, University of Ulm, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Moog
authors.forename: M
authors.initials: M
authors.lastname: Bangerter
authors.forename: C G
authors.initials: CG
authors.lastname: Diederichs
authors.forename: A
authors.initials: A
authors.lastname: Guhlmann
authors.forename: E
authors.initials: E
authors.lastname: Merkle
authors.forename: N
authors.initials: N
authors.lastname: Frickhofen
authors.forename: S N
authors.initials: SN
authors.lastname: Reske
mesh_terms: D000328:Adult; D001706:Biopsy; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D006689:Hodgkin Disease / Q000000981:diagnostic imaging*; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000000981:diagnostic imaging*; D008297:Male; D019275:Radiopharmaceuticals; D014055:Tomography, Emission-Computed; D014057:Tomography, X-Ray Computed
chemical_list: D005462:Fluorine Radioisotopes; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18